Hu Recom TNF-alpha, ACF, 100 µg

STEMCELL Technologies supplies an animal component-free preparation of recombinant human tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine that activates the NF-κB, MAPK, and PI3K/AKT signalling pathways. Activated T cells and macrophages are described as the primary producers of TNF-α in response to inflammation and infectious conditions, with additional production reported in B cells, NK cells, mast cells, neutrophils, dendritic cells, microglia, endothelial cells, smooth muscle cells, cardiomyocytes, and fibroblasts. The protein is also referenced under alternative names including cachectin and TNFSF2.

Among its biological effects, TNF-α is reported to exert cytotoxic activity on cancer cells in vitro by stimulating anti-tumour immunosuppressive responses, and to stimulate expression of E- and P-selectins, thereby facilitating adhesion of neutrophils, monocytes, and memory T cells to activated platelets and endothelial cells. Further documented effects include vasodilatation and oedema formation.

The protein is expressed in E. coli, has a predicted molecular mass of 17.5 kDa, and is provided lyophilised from a sterile-filtered aqueous solution containing sodium phosphate at pH 7.5. Reported quality attributes include a purity of ≥ 95% and an endotoxin level of ≤ 1 EU/μg protein, measured by kinetic Limulus amebocyte lysate (LAL) analysis. Specific activity is stated as ≥ 5.0 x 10^5 units/mg (EC50 ≤ 2 ng/mL), determined by induced cytolysis of L929 cells in the presence of actinomycin D, with a representative assay EC50 of 0.00877 ng/mL. The protein is reactive with mouse, rat, and monkey, and carries UniProt accession P01375. According to its safety data sheet, the preparation is not classified as a hazardous substance or mixture under GHS criteria. The supplier recommends storage at -20°C to -80°C, with stability of 12 months from the date of receipt when supplied. The lyophilised product should be reconstituted in sterile water to at least 0.1 mg/mL, pipetted gently down the sides of the vial without vortexing.